Denim Jackets -- Loaded Threat -- Help

Hope you all don't mind a noobie joining and starting a thread looking for help, without having contributed first. That said, I'll get right to it.

Got a new denim jacket from American Apparel -- cheap, like $80-90. I usually wear Mediums. However, for this denim jacket, the arm length of Mediums was ridiculously long, and I feel that where the sleeve ends is one of, if not the, most critical fitting aspect of a denim jacket. So, I went ahead and tried a Small. Boom. Perfect arm length -- cut right at the wrist.

I made a bit of an impulse buy, as I was kind of fiending for a denim jacket, even though they've been back in style for a couple years now. I figure I'll get one year of in-style out of it, and I mean they're pretty timeless -- right?

Anyways, the jacket is a little tight at the shoulders. Not egregiously so, but my ability to rotate my arms around is slightly limited. Length-wise it cuts right at my waist, so that's pretty choice too.

On to my questions:

1.) I'd like to stretch out the jacket width-wise, and maybe even just a pinch length-wise. From what I've read, the best way to stretch denim jeans is to soak in warm water and stretch them any way you can. I've just employed that tactic, and will probably give it a second wet-n-stretch later on. It's hang drying right now.

Any other tips on stretching a denim jacket?

2.) I want to wear t-shirts under it, but I wear Medium T's and they are considerably longer than the jacket. I see this is pretty common with denim jackets, but am afraid it will make me look like some punk teenager.

Thoughts?

3.) You all feel that denim jackets are "timeless", or as close to timeless as an article of clothing can be?

I'm not even considering taking it back or anything, and I'm pretty excited to integrate it into my weekend wear. I just need to make sure it's sharp as fuck.

1) I have no idea about methods of purposely stretching your denim. It just happens on its own right? I think if you just wear the shit out of it, it will stretch on its own.

2) Denim jackets are usually shorter than your t-shirts, yes. As long as the t-shirt itself isn't too long, this won't look funny. Your tees should hit 2-3 inches below the top of your pants, meaning they'll probably poke out the denim jacket about the same amount.\

3) Denim jackets are timeless. They are on-trend right now, but even if/when they go out of style, it's still something you should be able to throw on from time to time.

Bonus) I care about fit as much as the next guy, but you're over thinking this a little. Part of the appeal of denim jackets is that they're easy, go-with-anything pieces that you shouldn't have to try too hard to wear. Just start throwing it on with whatever and beating the hell out of it. My two cents anyway.